1. Field of the Invention
The present invention relates to a broadcast receiving device and a broadcast receiving method that simultaneously receive a terrestrial digital broadcast and an analog broadcast, for example.
2. Description of the Related Art
Terrestrial digital broadcasting started in 2003. Since the start of the terrestrial digital broadcasting, there have been an increasing number of cases where exactly same contents are transmitted by analog broadcasting and the terrestrial digital broadcasting simultaneously in a same time period. For example, FIG. 4 is a diagram showing an example of receiving two programs of analog broadcasting and digital broadcasting on two screens. A television receiver 41 in FIG. 4 can simultaneously receive two programs, that is, an analog broadcast program A indicated by 42 and a digital broadcast program D indicated by 43 in two picture areas on a screen. At this time, speakers 44 and 45 output the audio of the analog broadcast program A or the digital broadcast program D selected by the television receiver 41.
There is currently a broadcast receiver that allows manual audio level setting for each of terrestrial digital broadcasting, BS (Broadcasting Satellite) digital broadcasting, and terrestrial analog broadcasting. For example, FIG. 5 is a diagram showing an example of receiving two programs of terrestrial digital broadcasting and BS digital broadcasting on two screens. A television receiver 51 in FIG. 5 can simultaneously receive two programs, that is, a terrestrial digital broadcast program indicated by 52 and a BS digital broadcast program indicated by 53 in two picture areas on a screen. At this time, speakers 54 and 55 output the audio of the terrestrial digital broadcast program or the BS digital broadcast program selected by the television receiver 51.
In addition, a broadcast receiving device is proposed which stores a specified value of sound output volume for each channel, and when a receiving channel is changed, refers to the specified value, and automatically adjusts sound output volume to a corresponding sound volume (see Japanese Patent Laid-open No. 2001-54037, Patent Document 1).
However, in the above-described television receiver 41 shown in FIG. 4, at a time of program switching when the two programs, that is, the analog broadcast program A and the digital broadcast program D received on the two screens have identical contents, a difference between the sound volumes of the analog broadcast program A and the digital broadcast program D selected by the television receiver 41 may become noticeable. The audio of the analog broadcast program A or the digital broadcast program D is output from the speakers 44 and 45. It is thus difficult to say that a setting is convenient for users. There is also an inconvenience of having to manually set an audio level for each program.
In analog broadcasting, transmitting power is not specifically limited by standards, and therefore transmitting power differs for different broadcasting stations. On the other hand, in digital broadcasting, transmitting power is limited by standards. In addition, the transmitting power of the analog broadcasting is higher than the transmitting power of the digital broadcasting. This is a reason that there is a large difference in sound volume between the analog broadcasting and the digital broadcasting.
Further, even in a same digital or analog broadcasting format, the sound volume of a channel dedicated to movies or a channel dedicated to sports may be larger than that of a channel for other contents. This is another factor in sound volume difference.
In addition, the technique described in the foregoing Patent Document 1 needs a specified value of sound output volume to be stored for each channel. Since the digital broadcasting has a few hundred channels, there is an inconvenience of requiring a massive storage capacity.
It is accordingly desirable to provide a broadcast receiving device and a broadcast receiving method that can finely and automatically correct sound volume level not only for each broadcast but also for each program and each genre at the time of program switching, and which provide good usability for a user.